In our world, gin and cigarettes are luxury items that many people consume for pure enjoyment and that many people consume out of necessity, if an addiction develops in the person using them. In George Orwell's brilliantly dystopian novel 1984, these items offer little pure enjoyment. Their consumption is often described as a largely unsatisfactory experience. If they weren't the only brand available, I can't imagine people would choose them at all.
The first reference to Victory Gin describes it in detail: "It gave off a sickly, oily smell." Winston swallows it as one would "a dose of medicine," and it has a strong, unpleasant effect at first:
Instantly his face turned scarlet and the water ran out of his eyes. The stuff was like nitric acid, and moreover, in swallowing it on had the sensation of being hit on the back of the head with a rubber club. The next moment, however, the burning in his belly died down and the world began to look more cheerful.
Immediately following this passage is a description of the Victory Cigarettes, which are so poorly produced that the tobacco falls out when Winston tries to light one. Much later in the novel, we see that inner party members have better quality luxuries, including "very good cigarettes, very thick and well packed, with an unfamiliar silkiness in the paper."
The terms "Victory Gin" and "Victory Cigarettes" also make me think of similar terms such as "victory garden," mostly from World War I and World War II. Those terms turn everyday items and everyday routines on the homefront into significant actions that contribute to the war effort. In Orwell's novel, the country is perpetually at war, and these simple-named, poor quality brands of Victory Gin and Victory Cigarettes, produced by order of the state, feed addictions among the outer party members and turn consumption of even these flawed luxuries into a pro-government and pro-war action.